An estimated 50 million people in the U.S. have high blood pressure (systolic blood pressure [SBP] greater or equal to 140mmHg and/or diastolic blood pressure [DBP] greater or equal to 90 mmHg), or are taking antihypertensive medications. All factors considered and remaining constant, the incremental cost of treating 25 million patients with a drug costing $ 100 per patient-year of therapy compared to one costing $500 per patient-year of therapy is $10 billion. Hypertension (HTN) is considerably more common among African Americans than Caucasians, and its sequelae are more frequent and severe among African Americans. ALLHAT is a nationwide, practice-based, randomized, clinical trial of antihypertensive pharmacological treatments and cholesterol lowering--in a specific subset of 40,000 high-risk hypertensive patients including at least 55% African Americans. The purpose of the antihypertensive trial component is to determine whether the combined incidence of fatal coronary heart disease (CHD) and non-fatal myocardial infarction (MI) differs between diuretic (chlorthalidone) treatment and three alternative, more expensive antihypertensive pharmacologic treatments--a calcium antagonist (amlodipine), and angiotensin converting enzyme inhibitor(ACE-1) (lisinopril), and an alpha-adrenergic blocker (doxazosin). Because of the established benefit of antihypertensive treatment in reduction of stroke, total morbidity and mortality from cardiovascular diseases (CVD), and all-causes mortality, the antihypertensive trial component will not include a placebo. The purpose of the cholesterol lowering trial component is to determine whether lowering serum cholesterol in moderately hypercholesterolemic men and women aged 60 years and older with the 3-hydroxmethlglutaryl co-enzyme A (HMG CoA) reductase inhibitor pravastatin will reduce all-cause mortality as compared to a control group receiving "usual care." Secondary objectives of both trial components are to compare the effects of their respective treatment regimens on CV mortality, major morbidity, health costs, and the effects of their respective treatment regimens on CV mortality, major morbidity, health costs, and health-related quality of life. Additional secondary objectives of both trial components are to compare the effects of alternative treatments on all-cause mortality and on major HTN-related morbidity such as incidence and regression of left ventricular hypertrophy and progressive renal dysfunction. Additional secondary objectives of the lipid-lowering trial are to assess the longterm safety of HMG CoA reductase inhibitors in men and women aged 60 years and above (particularly with regard to mortality from non-CV causes), the effect of lipid-lowering on cancer incidence and mortality, and on the combined incidence of fatal CHD and nonfatal MI, especially in key subgroups (African Americans [self-described "blacks"], over age 65, women, type II diabetics). Mean duration of this trial is expected to be 6 years.